Pressure gauge



Jan. 5 1926.

D. EDGE ET AL PRESSURE GAUGE Filed Sept. 28, 1923 4 Sheets-Sheet 1 f 7 W 2% 5% k m i WJMSSBJ.

Jan. 5 1926.

D. EDGE ET AL PRES SURE GAUGE Filed Sept. 28, 1923 4 Sheets-Sheet 2 Vii/M8595.-

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Jan. 5 1926.

D. EDGE ET AL PRES SURE GAUGE 4 Sheets-Sheet 3 Filed Sept. 28, 1923 SOURCE OF WATT M ETE E CONSTANT VOLTAGE CURRENT fizventbr file-X756 065 and JOHN A. Hz/NTEB Jan. 5 1926. 1,568,140

D.EDGE ETAL PRESSURE GAUGE Filed Sept. 28, 1923 4 Sheets-Sheet 4 lia'Znezssea; 76097250219: X72764? [and 0; W j ge,

Patented Jan. 5, 19 26.

UNITED STATES A I 1,568,140 PATENT OFFICE.

nnxrnn anon, or rrr'rsnvnen, AND JOHN A. HUNTER, or BEN-AVON, mm.-

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PRESSURE GAUGE.

Application filed September 28, 1923. Serial No. 685,875.

I To all whom it may concern:

Be it known that we, 'Dnx'rnn Evan and JOHN A. HUNTER, citizens of the United States,'and residents, respectively, of Pittsburgh and Ben Avon, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Pressure Gauges, of which the following is a specification.

This'invention relates to pressure gauges and more particularly to pressure gauges for measuring the variations in flow of a fluid through a main or other conduit.

One object of the present invention is to provide a gauge that is especially adaptable to pulsating flow in pipe llnes, such as steam to a reciprocating engine, air from a reciprocating air compressor, etc., although it is not lin'nted to such uses but may be used equally well on a non-pulsating flow.

Another object is to provide a pressure gauge having an improved form of metallic diaphragm particularlyadapted for use in gauges of this class and which will bend more uniformly over its entire surface than diaphra s such as used in the prior art.

A sti further object is r to provide a pressure gauge having the novel design, construction, and combination of parts herein- I the gauge ofthis application.

after described, and illustrated in the accompanying drawings.

In the drawings Figure 1 is a sectional elevation through a pressure gauge and main, showing t e gau e in operative position.

Flgure 2 is a front end elevation thereof.

Figure 3 is a top plan thereof.

Figure 4 is a wiring diagram showing the operation of the watt meter.- 40

Figure 5 is a front and Figure 6 is a sectional elevation of the diaphragm used in to the drawings, the numerals 2.. and 3 esignate front and back body sections respectively, which Referring more particularl are in the form of flat plates relieved on their inner surfaces to form a working chamber 4:. A flexible metallic diaphragm 5 is clamped between the members 2 and 3 and serves to divide the working chamber 4 into two-parts.

The diaphragm 5 is of special construction and is formed from spring copper or other similar metal. In forming the diaphragm a suitable blank disk is formed of cular corrugations 6 are formed therein by s inning or otherwise working the metal.

ach successive corru ation, progressing towards the center of t e disk, is deeper and of slightly greater width than the preceding one, so'that, due to the fact that the corrugations are formed by spinning, the metal of the diaphragm will be progressively thinner towards the center, which will cause 1t to bend more uniformly over its entire surface.

The fluid to be gauged is adapted to be contained in a main 8 having a restricted flow passage 9 formed by an apertured disk 10. The respective sides of the working chamber are connected through orts or openmgs 11 and 12 and pipes 13 an 14 with the respective sides ofthe restricted flow passage so that the differential pressure will act on the diaphragm 5. The ports or openings 11 and 12 are preferabl formed in the lowermost portion of the c amber 4 so .as to continuously drain the chamber. However, if desired, they may be located at hi her points.

-' y having the working chamber 4 conaccelerated and moved more rapidly, so that the gauge follows a changing pressure differential instantaneously.

The diaphragm 5 has a suitable rack member 16 secured to the central portion thereof and projecting outwardly through the front body portion 2. The rack 16 is in mesh with a pinion 17 on a shaft 18 mounted in suitable bearings ina housing carried on the member 2. The shaft 18 is provided with a commutator brush 19 adapted to operatively contact with a commutator 20 which in turn is adapted to cut in and out successive banks of resistances 21.-- The commutator 20 and resistance banks 21 are supported on a suitable bracket 22.

The body portions 2 and 3 respectively, are drilled to form upwardly extending conduits 23 and 24 from, each s1de of the working chamber 4, and valves 25 and 26 are provided at the upper end of the respective conduits 23 and 24. The conduits 23 and 24 may be used as vents or may be used to introduce other liquid than that being metered, such as non-condcnsible gases which are lighter than the fluid being gauged.

A suitable by-pass and unloading valve 28 is mounted in a by-pass condult 29 ex tending between the conduits 23 and 24. The valve 28 is held against its seat by a spring 30 and by putting the proper initial compression on the spring 30 by means of the threaded stem 31, the valve can be made to automatically open at any predetermined value of the differential pressure, thus preventing the diaphragm 3 from be1ng ruptured because of excessive pressure differentials. Valve 28 can also be forced from its seat by operation of a threaded stem 32, thus forming a by-pass for zero ad ustment.

Suitable valves 33 and 34 respectively, are provided in the pipes 13 and 14 so as to permit the shutting ofi' of the gauge when desired. v

A suitable instrument board 35 containing a watt meter 36 is provided and connected electrically with the resistance banks 21, so as to integrate the flow variations.

The operation of the gauge is lllustrated in the wiring diagram of Figure 4, in wh1ch the numerals 37 and 38 indicate the lines leading from a source of constant voltage current. The line 37 is connected in series with the resistance banks 21 and then through the brush 19 to one side of the watt meter, while the line 38 is connected directly to the other side of the watt meter.

It will be readily seen that any movement of the diaphragm 5 will cause a movement of the brush 19 and thereby vary the resistance in the watt meter circuit, thus indicating the variation in the fluid flow.

We claim- '1. A differential pressure gauge comprising a two piece hollow body portion, a corrugated metallic disk diaphragm mounted vertically in said body portion so as to divide said body into two separate pressure chambers, said dia hragm being secured between the parts of said body, conduits connecting each of said chambers with sources of fluid pressure, means for regulating the flow through; said conduits, a horizontal rack member secured to the center of said diaphragm, a vertically disposed shaft, a

pinion on said shaft and meshed with said rack, said rack bein adapted to be reciprocated by said diap ra m when said diaphragm is deflected by the difference of fluid pressure in said chambers and to thereby rotate said shaft through said pinion, and electrical registering mechanism including a watt meter adapted to have a constant voltage electric circuit passed therethrough, a plurality of resistance banks, and a movable contact member for cutting said resistance banks into and out of the electric circuit passing through said meter, said contact member being actuated by said shaft.

2. A differential pressure gauge comprising a body portion composed of a pair of flat plates having their inside faces cut away to form a recess when said plates are secured together, a corrugated metallic diaphragm mounted vertically between said plates and extending parallel thereto so as to divide said recess into a air of working pressure chambers, con uits leading' for controlling the flow through said bypass, means for manually opening said last named valve when desired, and means operable by said diaphragm for registering the pressure chan es in said chambers.

3. In a di erential pressure gauge, the combination of a closed receptacle, a diaphragm dividin said receptacle into two chambers and a apted to be deflected to an extent varying with the difference between the fluid ressures in said chambers, conduits leadlng from said chambers to sources of fluid pressures, an upwardly extending conduit leading from the upper end of each of said chambers and provided with a valved outlet, said last named conduits serving as vents when desired and having a by-pass formed therebetween, an automatic pressure operated valve for controlling the flow through said by-pass, and means operable by said diaphragm for reg istering the pressure changes in said chamers.

In testimony whereof we have hereunto set our hands.

DEXTER EDGE. JOHN A. HUNTER. 

